The power of WWW is the linking of pages that reside on machines all over the world. Linking is doen by specifying the address of the page that is referenced. This address specification is also called the URL (Uniform Resource Location).
A URL contains a specification of type, of machine and directory path on that machine. For example:
in which the type is
If you reference to pages locally, that is on the same machine as the page with the link, then you may specify the directory path only:
It is also possible to specify relative paths, so if you reference from page /whoswho/whoswho.html to page /whoswho/ww-kittel.html, then the URL may look like:
For pages that belong together, relative addressing is very convenient, since you may copy a tree whith those page to another directory without having to modify the URL's referencing between these pages.
Specification of a link is done as follows:
where text-describing-linked-page will be underlined and will have the colour of a link, of a visited link (if previously referenced) or of an active link (if the link is being followed).